I understand you feel disappointed with your vets....and understandably so because you have had a nasty shock and are upset. However given what you have described I think
your vets made the best diagnosis upon the evidence available when they operated for a suspected cystic ovary. Whilst it turned out not to be a cystic ovary, the fact is, they would not have discovered it was actually a deep-seated abcess without performing the operation (unless they had access to, and you agreed to pay £400+ for, a CT Scan that would help them distinguish between the two prior to an op).
The really disappointing thing is that the abcess is so deep seated that they felt it could not be surgically removed SAFELY at the time - but again that would not have been discovered without the operation in the first place.
Given what has been discovered it is probably a good thing they spayed her at the time as there was a possible risk that the reproductive system could also become infected at a later date which could have resulted in an emergency spay for pyometra (or worse - a fatality).
Nevertheless - despite the operation - Dwynwen has gone through a surgical procedure and the "problem" still remains. My heart goes out to you - not only do you have the frustration that the operation may not have achieved anything (trust me it did achieve something for all the above reasons) but you now have to deal with what I regard to be one of the most unpleasant aspects of caring for a sick piggie........keeping a large abcess drained and flushed.
This is not for the faint-hearted - and I take my hat off to anyone (and I can think of a few members on this forum) who have undertaken the challenge. I wlil be sending you positive healing vibes and rooting for you all the way.
The only practical help I can offer is as follows:
a) As per
@furryfriends Excellent Adventure Sanctuary If the abx prescribed is baytril or septrin then I would consider going back and pressing for zithromax.
b) You may want to ask if it is possible to culture the abcess to identify the bug and what abx it is sensitive to. This does not always work with abcesses....but it is worth a try and could save a lot of time.
c) It may "take two" to treat an abcess depending upon where it is located - one to restrain the piggie and one to "do the flushing". With one of my piggies, it was not possible for me to flush the abcess properly on my own - so after a few days of trying I asked the vets to board her to do it properly for me. Also, with long term treatment of a piggy (for whatever reason - even if just multiple syringe feeds)..it can become very stressful and tiring for the slave...so I have sometimes asked my vets to board the pig for a few days to give me some "respite"
I will be watching and wishing you well......and the Pebble piggies are sending Dwynwen healing wheeks
xxxxx